Self-propelled toy boat



M. E. TOMAK El AL SELF-PROPELLED TOY BOAT Filed May 20, 1955 FIG.

March 19, 1957 INVENTORS Mm'ou E. TOMAK 5, ROBERTWGRlFl-ITHS BYMJ/W M ATTORNEYS United States Patent ce SELF-PROPELLED TOY BOAT Milton E. Tomak and Robert W. Gritfiths, Linton, Ind.

Application May 20, 1555, Serial No. 999,790

1 Claim. (Cl. 46--93) This invention relates to toy boats and more in particular to the type of toy boat propelled by a surface tension reducing medium.

Heretofore toy boats that have been propelled by means of surface tension reducing mediums have used solid material which on solution affects the water contacting the stern portion of the boat to propel the same. The material is usually in the form of a solid such as sugar, aerosol or a mixture. The solid material is placed within a recess within the stern portion of the boat, or if a liquid material is used it is introduced into a recess.

It is an object of the present invention to produce a toy boat having a transom at substantially right angles to the major axis across the stern portion thereof which affords the maximum propulsion force to the boat.

It is a further object of this invention to have the liquid fed by gravity through a free flowing conduit from the reservoir or tank to the center of the transom so that it will flow across the entire surface of the transom and exert a propelling force thereon.

These and other objects will be apparent from the description and drawing attached hereto wherein:

Figure 1 is a plan view of the boat.

Fig. 2 is a side View of the boat.

Fig. 3 is a section on line 3-3 of part of Figure 1.

Fig. 4 is an enlarged stern view of the boat.

Referring more in particular to the drawings wherein the hull ll of the boat is shown in Figures 1 and 2, the said hull is composed of any light weight material such as thermosetting plastic material. This boat is formed with a tank 11 on the stern thereof, which tank has an opening 12 to allow filling, and a conduit 13 is located at the rear part thereof. This conduit 13 as shown in Fig. 3 allows the liquid to flow under gravity through this opening and through the transom 14. The transom 14 is shown in an enlarged view in Figure 4 and extends across the stern of the boat and is as wide as the maximum width thereof.

In the preferred illustration shown in the drawings, the

Patented Mar. 19, 1957 transom 14 is supported by the side extensions 15, 15 so as to give a clean flow of water along the sides of the boat to the transom. This transom is not notched or recessed. it has a plane surface that contacts the water and is at right angles to the major axis of the boat so that when the surface tension is reduced it is reduced equally across the entire surface 14 of the transom and produces the maximum propelling power against the boat and this force is exerted at right angles to the major axis and tends to propel the boat directly forward.

The boat is provided with a rudder 16, shown in Figs. 2 and 3 which may be adjusted so as to have the boat travel in a circle or in any desired course.

It has been found that liquid propellants, 17 (shown in Fig. 3 only), such as ethyl alcohol or isopropyl alcohol, gives satisfactory results and it is readily seen by using a colored propellant that the liquid flows: across the entire surface of the transom and acts equally on the entire area thereof, as shown at 18 in Figure 4.

The conduit 13 from the tank to the transom is preferably of the free flowing type and allows the liquid to flow by gravity from the tank. It is desirable to have this conduit small enough so that a regulated flow of liquid is obtained, but it is not desirable to have an obstruction placed in this conduit, such as a wick or wire.

It has been found that the above described propelling means comprising a transom at substantially right angles to the major axis gives much better results than if the transom is broken so as to form a notch or recess in the center thereof as in that case the propellant liquid tends to act only across the opening in the transom and thereby reduces the effective area against which the force may act.

In the above embodiment of my invention a toy boat has been described. This novel propulsion means may be applied to any floating toy adaptable to its use and is limited only by the scope of the appended claim, wherein:

What I claim is:

A self-propelled toy boat comprising a hull adapted to be floated on water, said hull formed of light weight material having a tank above the water line containing a surface tension reducing liquid therein, a plane continuous transom at right angles to the major axis of the hull and a conduit extending from the tank through the transom above the water line.

References Cited in the file of this patent UNITED STATES PATENTS 2,439,649 Cohn Apr. 13, 1948 2,511,323 Briggs et al June 13, 1950 FOREIGN PATENTS 585,015 Great Britain Jan. 28, 1947 

